He entered at once into commercial life in Glasgow, and became a member of a kinsman's firm, William Kidston & Sons, iron merchants, subsequently joining William Jacks & Co., iron merchants.
Do you know how to make flap jacks?
All the subscribers' lines are connected in order to jacks on the first two or three or four operators' positions, and these connexions are repeated or " multipled " upon each succeeding similar group of positions.
Each subscriber's circuit is further connected to another spring-jack directly associated with the calling-drop. These springjacks, known as answering jacks, are distributed along the switchboard, a certain number being terminated upon each position and placed in the care of the operator assigned to that position.
In this arrangement, instead of the circuit being made through the jacks in series, each jack is connected to an independent branch from the main circuit.